import java.util.Objects;

class Money implements Cloneable{
    public double money;

    @Override
    protected Object clone() throws CloneNotSupportedException {
        return super.clone();
    }

    @Override
    public boolean equals(Object o) {
        if (this == o) return true;
        if (o == null || getClass() != o.getClass()) return false;
        Money money1 = (Money) o;
        return Double.compare(money1.money, money) == 0;
    }

    @Override
    public int hashCode() {
        return Objects.hash(money);
    }
}

class Student implements Cloneable{
    public int age;
    public Money m = new Money();

    public Student(int age) {
        this.age = age;
    }
    @Override
    public String toString() {
        return "Student{" +
                "age=" + age +
                '}';
    }
    @Override
    protected Object clone() throws CloneNotSupportedException {
        Student tmp = (Student)super.clone();
        tmp.m = (Money) this.m.clone();
        return tmp;
        //return super.clone();
    }

    @Override
    public boolean equals(Object o) {
        if (this == o) return true;
        if (o == null || getClass() != o.getClass()) return false;
        Student student = (Student) o;
        return age == student.age && Objects.equals(m, student.m);
    }

    @Override
    public int hashCode() {
        return Objects.hash(age, m);
    }
}
public class Test {

    public static void main(String[] args) {
        Student student1 = new Student(10);
        Student student2 = new Student(10);
        System.out.println(student1.hashCode());//对象
        System.out.println(student2.hashCode());
    }

    public static void main4(String[] args) {
        Student student1 = new Student(10);
        Student student2 = new Student(10);
        System.out.println(student1 == student2);
        System.out.println(student1.equals("fafsfsa"));

        String s = "123456";
        System.out.println(s.equals("123456"));
    }

    public static void main3(String[] args) {
        Student student1 = new Student(10);
        Class<?> c = student1.getClass();
        System.out.println(c);
    }

    public static void main2(String[] args) throws CloneNotSupportedException {
        Student student1 = new Student(10);
        student1.m.money = 19.9;
        Student student2 = (Student) student1.clone();

        System.out.println(student1.m.money);
        System.out.println(student2.m.money);

        System.out.println("==================");

        student1.m.money = 29.9;
        System.out.println(student1.m.money);
        System.out.println(student2.m.money);

    }

    public static void main1(String[] args) throws CloneNotSupportedException {
        Student student1 = new Student(10);
        Student student2 = (Student) student1.clone();
        System.out.println(student1);
        System.out.println(student2);
    }
}